The surest way to protect the United States from a high-altitude EMP is by deploying a ballistic missile defense system that can intercept and destroy a warhead before it could be detonated above the U.S. This would prevent an EMP attack and eliminate any potential harm to U.S. systems, and it could even deter rogue leaders from considering the use of EMP.
Regardless of the debate, the surest way to protect the United States from a high-altitude EMP is to deploy a ballistic missile defense that would give the United States an opportunity to intercept and destroy a warhead before it is detonated above the atmosphere.